Abstract
Our objective was to explore if creatine kinase (CK) levels correlate with survival in amyotrophic lateral sclerosis (ALS), and whether a correlation is independent of other well-studied predictors such as location of onset, gender, age, fat free mass, spasticity, cramps, and fasciculations. We analyzed data from 80 ALS patients from a 48-week non-interventional longitudinal multicenter nutrition study with long term follow-up. The overall mean CK was 214 ± 191.8 U/l (range 22–1992 U/l). Forty-five percent of patients had at least one high CK value (> 200 U/l), and about half maintained a high CK value, but there was no trend over the study period. Male gender and extremity onset were significantly associated with high CK. In univariate analysis, age, bioelectric impedance spectroscopy (BIS) fat free mass, spasticity, and fasciculations were not associated with CK level. There was an association between CK and muscle cramps (p < 0.001). In survival analysis, low CK (≤ 200 U/l) was associated with a longer overall survival (p = 0.02), when adjusting for location of onset, age, race, gender, BIS fat free mass, and study site. In conclusion, CK may be a useful marker for ALS survival, which has implications for clinical care and the design of future clinical trials.
Acknowledgements
The University of Kentucky's multicenter nutrition study was funded by the National Institute of Neurological Disorders and Stroke, the ALS Hope Foundation, and the Cynthia Shaw Crispen Endowment. Research reported in this publication was additionally supported by the National Center for Advancing Translational Sciences of the National Institutes of Health. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.
Declaration of interest: The authors declare no conflicts of interest in the present study.
Supplementary material available online
Supplementary Figures 1–2 to be found online at http://informahealthcare.com/doi/abs/10.3109/21678421.2015.1062516.